Torpedo chaser, 1944

This "Torpedofangboote" seems to be a small torpedo chaser of 1944 vintage.
I believe boats like this drew miscellaneous harbor duties in addition to their
nominal role of chasing down and recovering torpedos fired in practice.

You have correctly described the purpose of these ships. The plan shows the TF 9 type that
was built in the Netherlands; the plan was issued by Wilton-Fijenoord, a yard in Rotterdam,
who built TF 15 - 18 between 1942 and 1944.
A total of 16 of the type (TF 9-24) were finished, another 12 (TF 25-36) were cancelled.

In addition to Wilton-Fijenoord, these ships were built by Nederlandse Dok, Amsterdam;
Van der Giessen, Krimpen; Rotterdamsche Droogdok; Nederlandse Scheepsbouw, Amsterdam,
all yards also engaged in the Mboot 40 minesweeper program.

Eight of the TF 9 boats survived the war. All this info comes from my indispensible Concise Gröner (Die Schiffe der deutschen Kriegsmarine und ihr Verbleib = The ships of the German Kriegsmarine and their fate). From a remark in Gröner, it seems that this design was derived from the
1916 type AIII small torpedo boats that you'll find as Torpedoboot 1916 on german-navy.de.